Beds usually contain a head board and a mattress which is supported by either a box spring or a flat spring unit. A box spring is a large mattress-sized box containing wood and springs that provide additional support and suspension for the mattress. In some beds, the box spring is supported by slats held by side rails which are connected to the headboard and a foot board. Other beds contain no foot board or side rails but instead have a self supporting metal frame which may be connected to a head board if desired.
Still other beds, including most twin beds or bunk beds, contain a head board, a foot board, and a flat spring unit rather than a box spring.
The head board and foot board commonly contain two wooden posts with horizontal slats connecting the posts together. Often the term “headboard” refers to both the headboard and footboard, since they are identical or similar in dimension. Moreover the bunk beds can optionally be stacked one on top of another for form bunk beds and save space. It is also common to mount the headboards on extenders so that the bed will be elevated providing space beneath the bed for desks, trunks, and the like. The wooden headboards are usually fabricated from two posts and at least one crosspiece extending between the posts by doweling and gluing or by mortise and tenon joints. It is not uncommon with heavy use such as in dorms for the joints to become loose after a period of time.
The bed frames are usually fabricated from angle iron side rails and end rails welded together in a rectangle with one or more reinforcing members extending between the side rails. Springs and/or wires are typically strung between the rails to support a mattress thereon. The flat spring unit includes a peripheral frame and, typically, a support structure stretched inside the peripheral frame and supported by springs connecting the support structure to the rectangular peripheral frame. The support structure is often a wire mesh wherein wire members bent into links which cooperatively engage one another to form a two dimensional mattress supporting mesh. Other flat spring units may include springs stretched across a peripheral frame. A side rail mounting bracket is riveted or welded to each distal end of a side rail at each corner of the bed frame and adapted to include hooks which cooperatively engage and hang on pins which extend across the lateral face of a longitudinal U-shaped channel members disposed in a vertical channel or groove formed in each corner post of a headboard/footboard.